An automobile brake assembly is one of the important parts to ensure the safe driving of the automobile, which directly affects the parking reliability and driving safety of the automobile. While a automotive brake fatigue test stand is the key testing equipment for the automotive brake assembly.
A conventional automobile brake assembly fatigue test stand is mainly composed of four parts, including a base, a power source mechanism, a torque measuring mechanism and a brake assembly tooling fixture. Normally, the power source mechanism is fixed on the base, and the torque measuring mechanism can slide on guide rails. Taking a drum brake assembly for example, the working principle of the fatigue test stand is as follows: the brake drum is connected with a brake drum tooling and fixed on the power source mechanism, and the brake is connected with the brake tooling and fixed on the torque measuring mechanism. During a fatigue test, the torque measuring mechanism slides on the guide rails to a specified position, and the power source mechanism drives the brake drum to rotate. When braking, the torque measuring mechanism measures the actual braking torque during the braking process. However, the conventional fatigue test stand has several defects as follows: (1) during the testing process, sliding guide rails of the torque measuring mechanism are subjected to a torque repeatedly, if a common ball linear guide rail is selected, the guide rail is easily to be damaged, if a dovetail groove type guide rail is selected, a friction during moving is greater than that of the common ball linear guide rail, so that a motor having a greater power needs to be selected. (2) A brake tooling clamp and a brake drum tooling clamp are relatively independent, and equivalent to two cantilever beam structures, which greatly affect the rigidity performance of the tooling fixtures, and even cause a situation that the brake has been contacted with the brake drum without braking, so that the stability during the testing process is relatively poor. (3) The conventional fatigue test stand can only complete the fatigue test at a room temperature, but cannot complete fatigue tests of the brake at other temperature conditions.
The patent with an application No. 201420692146.2 discloses a brake assembly static torsional strength test tooling, the solution of which expands the universality of the test stand through exchanging the tooling, but does not solve the problem of affecting the rigidity performance of the tooling. The patent with an application No. 201320738681.2 discloses a pneumatic disc brake stand test tool. A mandrel is additionally arranged between two tooling fixtures, one end of the mandrel is provided with a bearing inserted into one of the toolings while the other end thereof is connected with the other tooling through a screw. As the mandrel needs to play a role of increasing the rigidity, tight fit is needed for inserting the bearing into the tooling, but this structure is not convenient to disassemble. In addition, a brake caliper in the patent is connected with the mandrel, and the mandrel is easily damaged by the braking torque.